Field of the Invention
The invention relates to a manufacturing method of a circuit structure, and more particularly, relates to a manufacturing method of a circuit structure embedded with heat-dissipation block.
Description of Related Art
In recent years, for expanding applications of a printed circuit board (PCB), many technologies have been proposed to manufacture the printed circuit board in a multilayer circuit structure in order to increase spaces inside the multilayer circuit structure for circuit layout. A manufacturing method of the multilayer circuit structure includes repeatedly bonding and stacking build-up structures composed of a copper foil and a prepreg (pp) on a core board to increase internal circuit layout spaces in the multilayer circuit structure, and filling conductive materials into blind holes of each of the build-up structures by utilizing an electroplating process in order to conduct through each layer. In addition, various different components (e.g., chips, connectors, optoelectronic components or heat-dissipation components, etc.) may also be disposed in the circuit structure based on demands, so as to increase functionality of the circuit structure.
Take an electronic component (e.g., a chip) disposed in the circuit structure for example, because the electronic component will generate heat during operation, a heat-dissipation block is usually further disposed in the circuit structure for transferring heat energy to the outside of the circuit structure. Further, in order to provide better heat dissipation efficiency, a heat sink may also be disposed in the circuit structure to assist in heat-dissipation. In the conventional manufacturing method of circuit structure embedded with heat-dissipation block, the heat-dissipation block is generally embedded into a through hole penetrated the circuit structure only after a completed circuit structure is formed by bonding the build-up structures on the core board. Accordingly, a dimension of the heat-dissipation block is greater to cause increases in required manufacturing costs, and a heat-dissipation path of the heat-dissipation block is also longer. In addition, because the components (e.g., the electronic component, and the heat sink, etc.) are usually directly disposed on an outer surface of the circuit structure and connected to the heat-dissipation block, an assembly thickness may become thicker after aforesaid components are assembled into the circuit structure, which is disadvantageous in miniaturization of the circuit structure.